I'm thinking about creating and populating posts with a new tag, eye_contact_while_fellatio, which is for when eye contact happen between the giver and the receiver of fellatio.

The question is: is it a good idea? Some posts when searching eye_contact fellatio give false positives.

It would be better phrased as eye_contact_during_fellatio

But regardless, I think this is too specific, I really don't see very many false positives in eye_contact fellatio outside of a lot of mistagged looking at viewer posts (which is a problem with eye contact in general).